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Layer dependent band dispersion and correlations using tunable Soft X-ray ARPES

N. Kamakura·Y. Takata·T. Tokushima·Y. Harada·A. Chainani·K. Kobayashi·S. Shin
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Abstract

Soft X-ray Angle-Resolved Photoemission Spectroscopy is applied to study in-plane band dispersions of Nickel as a function of probing depth. Photon energies between 190 and 780 eV were used to effectively probe up to 3-7 layers. The results show layer dependent band dispersion of the Delta_2 minority-spin band which crosses the Fermi level in 3 or more layers, in contrast to known top 1-2 layers dispersion obtained using ultra-violet rays. The layer dependence corresponds to an increased value of exchange splitting and suggests reduced correlation effects in the bulk compared to the surface.

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N. Kamakura, Y. Takata, T. Tokushima, Y. Harada, A. Chainani, K. Kobayashi, S. Shin. 2004-04-21. Layer dependent band dispersion and correlations using tunable Soft X-ray ARPES. https://doi.org/10.1209/epl%2Fi2004-10052-6

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